1. Field of Invention
The invention relates to an analyzer for detecting the amounts of components contained in a sample.
2. Related Art
As an analyzer for detecting the amounts of components contained in a sample, a spectroscopic analyzer is widely employed whereby a sample solution is irradiated with white light such as emitted by a halogen lamp. The light beam that has passed through the sample solution is split by a diffraction grating to extract necessary wavelength components, and the amounts of target components are measured by determining their absorbance. The light emitted by e.g., a halogen lamp, however, cannot be narrowed in order to obtain an intensity of light commensurate with a sample solution that has been thinned by reducing its volume. Thus, there is a limit to the extent to which the amount of a sample solution can be reduced.
In response, it has been proposed to use a semiconductor light source capable of producing a narrowed light beam with sufficient intensity for a sample solution that has been thinned by reducing its volume. For example, JP Patent Publication (Kokai) No. 8-122247 A (1996) discloses an analyzer comprising a laser or LED element as the light source, whereby a sample container is irradiated with light beams of a plurality of wavelengths, and absorbance is measured in a plurality of wavelength regions. In another example, JP Patent Publication (Kokai) No. 2001-159601 A discloses that a plurality of semiconductor light sources, such as LEDs or laser diodes, are used, and a sample container is irradiated with light beams such that the optical axes of a plurality of light beams are aligned into one axis using an optical mechanism including a combination of prisms and half mirrors. Further, JP Patent Publication (Kokai) No. 2002-340676 A discloses that a sample container is irradiated with light emitted by a plurality of LEDs with the emission wavelength λn modulated with different frequencies fn, wherein transmitted light is A/D converted and then integrated for frequency analysis.
Patent Publication 1: JP Patent Publication (Kokai) No. 8-122247 A (1996)
Patent Publication 2: JP Patent Publication (Kokai) No. 2002-340676 A
Patent Publication 3: JP Patent Publication (Kokai) No. 2001-159601 A